PROJECT SUMMARY/ABSTRACT The Environmental Mutagen Society (EMS) was founded in 1969 to provide a forum for the establishment and support of scientists in the field of environmental mutagenesis. The mission of the Society is (1) to foster scientific research and education on the causes and mechanistic bases of DNA damage and repair, mutagenesis, heritable effects, epigenetic alterations in genome function, and their relevance to disease, and (2) to promote the application and communication of this knowledge to genetic toxicology testing, risk assessment, and regulatory policy-making to protect human health and the environment. For the past 40 years, EMS members have made many of the most important discoveries pertaining to the mechanisms of the induction of mutations, the roles of DNA repair defects and resulting mutations in toxicology and disease susceptibility, and the challenges of assessing risks from environmental exposures to mutagens. Recognizing the importance of its diverse mix of professionals to exchange ideas and the latest experimental findings, the EMS held its first meeting in Washington, DC on March 22-25, 1970, and has continued this tradition by providing a venue for these professionals to meet annually. Each year, the EMS Annual Meeting Program Committee strives to represent the full spectrum of strengths of the Society, encompassing most of the areas of current research that converge on the issues of environmental exposure and how cells and organisms respond to such challenges. In this proposal, we are requesting funds to defray part of the expenses for 2009 -2013 EMS Annual Meetings. The 2009 Program Committee of the EMS arranged for an outstanding and expansive scientific program that includes 17 symposia, 2 Saturday workshops, 5 plenary lectures, 2 poster sessions, and 4 platform sessions. In addition to the scientific program, the Annual Meeting will convene 8 Special Interest Groups (SIGS) that have the responsibility of identifying fore-front speakers and topics for the 2010 and subsequent meetings.